June, 1921. 



SCIENTIFIC AGRICULTURE. 



263 



t;ie occurrence of apparently cpp'halotriehic bacteria 

 among: the peritrichic cells of Bimllus radicicola and 

 li. radiobncter. That lihere exists no truly polar 

 flagellation in these eases, however, h evidenced by 

 the fact that the cilia composing .suclhi an apparently 

 polar tuft do not protrude exactly from the same 

 spot, as they do, for example, in the cell with several 

 polar flagella s^iown in Plate 68, A. They are always 

 more or less separated and are only accidentally 

 drawn together in the course of tdie shrinking of the 

 cajwule. A tlhorougji examination of well-made pre- 

 parations leaves no doubt that tlu^ original position 

 of the flagella is peritrichic. 



SUMMARY. 



(1) The nodule bacteria of the legruminous plants 

 are to be divided into two groups, differing morplio- 

 logically as well as pjiy.siologically. 



(2) The first group shows all features characteristic 



of Bacillus' radicicola Beijerinck. It is peritTieliic, 

 grows relatively fast on agar plates, and changes the 

 milk in a very dharaeteri.stic manner. It produces 

 nodules on the roots of the following plants: clover, 

 .sweet clover, alfalfa, vetch, pea, navy Ix-an, lupine, 

 black locust, Anuirpha, and Strophostyles. 



{'.)) The second group is characterized by mono- 

 tric.hic flagellation, comparatlively very slow growth 

 on agar plates, and inability to caiLse a marked change 

 in milk. It has been i.solated from eowpea, soybean, 

 peanut,- beggarweed, Acacia, Genista, and Cassia. 



(4) According to the cu.slwmary manner of clas.si- 

 fying bacteria, this second group of nodule bacteria 

 would have to be considered to be a new species, 

 and according to tihe rules of priority, it would have 

 to be named PscKdmnonas japonica or Bacterium ja- 

 ponicum (Kirclnier). But we do not advocate stich 

 a procedure, because only a complete study of the 



PLATE 69. 



A. — Mannite-nitiate agar slants, 8 days old. from left B. — Growth in milk. 4 weeks old from left to right: 



to right: soybean bacteria, vetch bacteria, and Bacillus soybean bacteria, vetch bacteria, and B. radiobacter. 

 radlobacter. C. — Growth on potato. 2 weeks old: vetch bacteria (left) 



and B. radiobacter cright). 



